PROJECT SUMMARY/ABSTRACT Type 2 diabetes in youth is a growing public health concern, with evidence that it is even more serious in youth than in adults, and a serious concern in minority and poor communities. A large clinical trial, known as TODAY, has been ongoing and will continue for 5 years. In the TODAY study, youth with type 2 diabetes were treated using three different treatment regimens. Now they are being followed every year to learn how their disease progresses and what factors contribute to poor outcomes (TODAY2). When TODAY started, these youth were less than 18 years of age, but now most of them are considered to be ?emerging adults,? in a phase of life during which these young adults must manage many changes, in addition to a serious disease. This study is designed to better understand the challenges and barriers to engaging in healthy behaviors these emerging adults with type 2 diabetes face, especially challenges in taking their medications, and attending healthcare visits. Our specific aims are to develop a full and rich understanding of factors related to medication adherence and healthcare visit attendance, and their relationship to diabetes health outcomes. We will recruit TODAY2 participants (N=350) to take part in this ancillary study at their annual TODAY2 visit. If they agree to participate, they will complete questionnaires (about their attitudes, beliefs, and behaviors), participate in unannounced pill counts (to measure their medication adherence), and agree to share other information that is routinely gathered for the TODAY2 study (for example, their blood glucose control levels). They will be assessed two times, one year apart. A subset of them (n=60) will also participate in interviews with trained research staff to describe their experience of living with type 2 diabetes. These data and themes that emerge from the interviews will provide important insights into how they cope and manage their diabetes. By understanding emerging adults with type 2 diabetes better, we will move towards the long term objectives of being able to provide meaningful guidance for the development of interventions that can help them achieve successful diabetes self-management, and for the public policies to support them.